This invention relates to a sensitive inclinometer which accurately measures very small angles relative to vertical. Such a device may be used in widely diverse fields and with any structure whose angular position must be precisely determined. One such application is in the field of hospital beds where it is desirable to tilt such a bed to different tilt angles and in both of the tilt directions, namely head-up and foot-down or vice-versa. For example, when a patient occupying a bed goes into shock, the bed should immediately be tilted to a trendelenburg position which has a specific tilt angle with the patient's head below his legs. The inclinometer of the present invention is especially useful when incorporated in a hospital bed to measure its tilt angle and tilt direction.
Previously developed inclinometers, capable of accurately measuring small deflection angles, are of complex and expensive construction. The present inclinometer, on the other hand, achieves very precise angle measurements and yet exhibits a unique construction which is relatively inexpensive and yet extremely reliable and rugged.